Field of the Invention
The present invention relates to a keyboard musical instrument that has auto-play capability.
Description of the Related Art
In keyboard musical instruments that have auto-play capability, it is necessary to minimize any error in a string-striking mechanism (action mechanism) that may occur as a result of manufacture or that develops over time due to aging, so as to maintain a desired operation of the string-striking mechanism. With a view to reducing any such error, Patent Document 1 (Japanese Patent Application Laid-Open Publication No. 2014-21233), for example, discloses a keyboard musical instrument in which key motion and string strike are detected by use of optical sensors that each include light emitting elements and light receiving elements for effecting servo control of key movement so that a trajectory of a hammer closely matches a target trajectory.
It is noted, however, that the invention set out in Patent Document 1 is subject to a drawback in that the configuration of the keyboard musical instrument is complex, since there is provided individually for each key of a keyboard, a(n optical) sensor that detects key motion and a(n optical) sensor that detects hammer motion. To overcome this drawback, an object of the present invention is to enable effective adjustment of movement of a string-striking mechanism by use of a simple configuration.